Gastric and duodenal ulcers affect a significant portion of the human population worldwide. Currently, the usual treatment for both gastric and duodenal ulcers involves treatment of the patient with histamine H.sub.2 receptor antagonists (H.sub.2 blockers). While the H.sub.2 blocker therapy is generally effective in healing ulcers, ulcer relapse occurs in up to 90% of patients within a year of discontinuing the therapy. Thus, patients must continue the treatment for many years or risk a recurrence of the ulcer. It is now known that ulcer healing drugs such as colloidal bismuth subcitrate (CBS) are helicobactericidal and that such CBS is used in combination with H.sub.2 blockers to treat ulcers. Additionally, CBS, an H.sub.2 blocker and amoxicillin have been used in combination to treat ulcer patients.
Helicobacter pylori has been recently demonstrated to be a major causative agent in gastric and duodenal ulcers and other gastroduodenal disorders, diseases and adverse conditions. Thus, antibiotic therapy to eliminate Helicobacter pylori from the gastroduodenal tract would remove the root cause of said gastroduodenal disorders, diseases and adverse conditions and eliminate the need for an ulcer patient to continue long and costly treatment with H.sub.2 blockers and the like. None of the foregoing treatments are capable of 100% eradication of Helicobacier plyori. Therefore, it would be desired to provide a compound having an excellent helicobactericidal activity.
The object of the present invention is to provide novel quinolone compounds having an excellent helicobactericidad activity and a pharmaceutical composition comprising the same. Another object of the present invention is to provide processes for producing the novel quinolone compounds.